Nucleotide sequences coding an endopolygalacturonase inhibitor

ABSTRACT

The gene coding for a fungal endopolygalacturonase inhibitor (PGIP) is cloned and sequenced from both Phaseolus vulgaris genomic and cDNA libraries. The PGIP amino acid sequence, vectors comprising the PGIP gene or parts thereof, and cells transformed by said vecors are also disclosed. 
     This isolated sequences are useful to transform plants, which are sensitive to fungi or microorganism pathogen activities, into plants producing the PGIP protein.

BACKGROUND OF THE INVENTION

This invention relates to nucleotide sequences coding a endopolygalacturonase inhibitor.

More particularly, this invention relates to a gene coding a new protein having an inhibiting activity against the fungal endopolygalacturonase enzyme, or fractions thereof, and to the protein itself or fractions thereof. The invention relates also to recombinant vectors comprising such sequences, to cells and plants transformed by means of such recombinant vectors and to the use of such vectors and cells to produce the protein.

References are listed at the end of the specification in the order cited.

The fungal endo alpha-1,4-D-polygalactorunase enzyme (EC 3.21.15) is an important pathogenic factor for plants (1,2). The enzyme catalyzes the scission reaction of polygalacturonic acid and induces the subsequent solubilization of plant cell wall homo-alpha-1,4-D-galactorunanes, thus facilitating the penetration of fungi into plant tissues and then supplying the same fungi with nutritional substrates.

Moreover, the activity of such an enzyme could, if controlled, produce non-virulence factors, i.e. factors able to activate some plant defence mechanisms by converting plant cell wall homogalactorunanes into oligogalacturonides, which are known to stimulate phytoalexin synthesis and other defence mechanisms as well (2).

An inhibiting activity of fungal endopolygalacturonase, associated with the cell wall, named PGIP, has been detected in dicot plants.

The authors of the present invention have already detected such activity in different plant tissues of Phaseolus vulgaris L. (3), showing that it is specific for fungal endopolygalacturonases, with no activity against either bacterial or plant enzymes, or other pectic enzymes of microbial origin (4), Moreover, the authors found that the PGIP is able to stabilize in vitro and oligogalacturonide mixture which stimulates phytoalexins (5).

Therefore it is evident the need to purify and isolate the molecule responsible for such activity by means of cloning coding PGIP sequences. Said sequences may be inserted in suitable vectors to transform plants that are sensitive to fungi or other microorganism pathogens, into plants producing the PGIP protein on large scale. The protein could be then used with many advantages in the food industry.

SUMMARY OF THE INVENTION

Prior attempts to isolate the PGIP gene have been unsuccessful, essentially due to low levels of the protein in plant tissues.

The authors of the invention have now isolated and sequenced the PGIP protein coding DNA, both from a genomic and cDNA library, and have also identified the amino acid sequence of the PGIP protein.

An object of the present invention is a DNA fragment comprising a sequence coding a PGIP protein having an inhibiting activity of the fungal endo-alpha-1,4-D-polygalacturonase enzyme (PG), or parts thereof. Preferably said DNA fragment is of plant origin, more preferably isolated either from plants, or parts of plants, or in vitro cultured plant cells of the Phaseolus genus, most preferably of the Phaseolus vulgaris species.

According to a preferred embodiment said DNA fragment codes for a PGIP protein having the amino acid sequence of SEQ ID N15, or parts thereof. Alternatively said amino acid sequence SEQ ID N15 lacks or is substituted of one or more amino acids, preferably is a variant of a PGIP protein, more preferably said variant of a PGIP protein comprises the amino acid sequence SEQ ID N17, or parts thereof.

According to another embodiment said DNA fragment comprises the nucleotide sequence of SEQ ID N14, consisting of:

a coding region from nucleotide 1 to nucleotide 1026;

a 3'-end untranslated sequence from nucleotide 1027 to nucleotide 1116.

Alternatively said nucleotide sequence lacks or is substituted of one or more nucleotides, preferably comprising the nucleotide sequence of SEQ ID N16.

Another object of the invention is a DNA fragment hybridizing to at least one of DNA fragments having the sequences above described, preferably complementary to them.

Another object of the invention is a DNA fragment comprising an allele of either SEQ ID N14 or SEQ ID N16 sequences.

All of the DNA fragments according to the invention may be derived from either a genomic library, or a cDNA library or in vitro synthesis.

Another object of the invention is a substantially purified PGIP protein having an inhibiting activity for the fungine PG enzyme and being of natural or recombinant origin, or parts thereof. Preferably said substantially purified PGIP protein derives from plants, parts thereof or cultured plant cells, more preferably of the Phaseolus genus, most preferably of the Phaseolus vulgaris species.

According to a preferred embodiment said protein comprises the amino acid sequence of SEQ ID N15, or parts thereof, alternatively said protein lacks or is substituted of one or more amino acids, preferably said protein comprises the amino acid sequence of SEQ ID N17.

Another object of the invention is a recombinant vector comprising any one of the nucleotide sequences of the invention, preferably of plasmid or phage origin, more preferably said recombinant vector is the pAD-1 plasmid (DSM N.6821).

In a preferred embodiment said recombinant vector comprises a promoter able to express said coding PGIP nucleotide sequence, preferably said promoter is active either in bacteria, or in yeasts, or in higher plants.

Other objects of the invention are cells transformed by one of the vectors above described, preferably said cells are bacterial cells, more preferably belonging to the Escherichia coli species. Alternatively said cells are eukaryotic cells, preferably yeast cells, alternatively plant cells.

A further object of the invention is a process for isolating and cloning PGIP protein coding sequences, or parts thereof, comprising:

partial sequencing of the amino acid sequence of the PGIP protein;

in vitro synthesing oligonucleotides, the sequence of which is derived from said amino acid sequence;

probing a genomic or a cDNA library from plant cells with said oligonucleotides, previously labelled;

isolating positive clones, extracting the recombinant vector from a positive clone and identifying the recombinant insert from said recombinant vector;

sequencing said recombinant insert.

The invention shall be illustrated in the following examples by making references to some preferred embodiments, completed with the following figures where ;

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows the PGIP elution profile on Mono S column;

FIG. 2 shows an agarose gel electrophorosis of amplified DNA, using the following primers: A: mol weight markers; B: control; C: N-A and Int; D: N-B and Int; E: N-A; F: N-B;

FIG. 3 shows a map of primers and of amplified DNAs;

FIG. 4 shows a restriction map of lambda PGIP-3.3 and of pPT-2;

FIG. 5 shows a hydrophobicity plot of the PGIP protein;

FIG. 6 shows a Northern blot by using RNAs from different plant tissues, probed with a radiolabelled pPT-1 fragment;

FIG. 7 shows a comparative analysis of PGIP coding sequences isolated from two different cultivars of Phaseolus vulgaris species.

DETAILED DESCRIPTION OF THE INVENTION EXAMPLES Example 1 Purification and Sequencing of PGIP Protein

Plants of Phaseolus vulgaris L., Pinto cultivar, are grown on vermiculite under 18 hour light exposure conditions. The callus and cell suspension cultures from Pinto cultivar are obtained as described in (3).

The PGIP protein is purified from hypocotyls (30 μg/kg of fresh weight) by affinity chromatography on Sepharose coupled to endopolygalacturonase, as described in (6). One unit of PGIP protein is the amount able to reduceof 50% the activity of one unit of endopolygalacturonase, isolated from Aspergillus nidulans.

PGIP is then diluted at 1:4 ratio in 30 mM. Hepes pH 7.5 buffer, and loadedon Mono S column (Pharmacia), equilibrated with the same buffer. The protein is eluted with a linear gradient 0-0.3M NaCl in 20 mM Hepes pH 7.5buffer. Approximately 90% of the loaded material having a 280 nm absorbanceelutes with the excluded volume, showing no PGIP activity at all. The remaining 10% elutes with a single peak at a 0.1M NaCl and shows PGIP activity (FIG. 1). Fractions containing PGIP activity are collected and loaded again on Mono S column to concentrate the protein to 35 μg/ml.

5 μg of the protein are used to determine the N-terminal sequence, according to standard methodology. The remaining amount is digested by 1 mg/ml of TPCK (Sigma) treated trypsin in 1.0M ammonium bicarbonate pH 7.8 buffer, at 37° C. for 16 hours. The resulting peptides are separated using a binary gradient (solvent A: 0.1% TFA in water; solvent B: 0.085% TFA in 80% aqueous CH₃ CN) at a flow rate of 0.2 ml/min. Single peaks are collected, dried, dissolved in 50 μl of solvent A and chromatographed again on the same column.

Peptides, as well as the undigested PGIP protein, are sequenced by a ABI 470A or 477A sequencer. Aminoacid sequence of the N-terminal fragment and of four tryptic fragments of the PGIP protein are shown in the Table 1 hereinbelow.

                  TABLE 1                                                          ______________________________________                                         Aminoacid sequence of the N-terminal fragment and                              of four tryptic peptides of PGIP protein                                       Residue                                                                        number   N-terminal                                                                               P-1      P-2   P-3   P-4                                    ______________________________________                                          1       Glu       Ile      Leu   Ile   Ile                                     2       Leu       His      Phe   Tyr   Ser                                     3       X         Leu      Thr   X     Gly                                     4       Asn       Ala      Ser   Thr   Ala                                     5       Pro       Lys      Met   Leu   Ile                                     6       Glu(n)                   Pro   Pro                                     7       Asp                      Gln   Asp                                     8       Lys                      Gly   Ser                                     9       Glu(n)                   Leu   Tyr                                    10       Ala                      Thr   Gly                                    11       Leu                      Gln   Ser                                    12       Leu                      Leu   Phe                                    13       X                        Lys                                          14       Ile                                                                   15       Lys                                                                   16       Lys                                                                   17       Asp                                                                   18       Leu                                                                   19       Gly                                                                   20       Asn                                                                   21       Pro                                                                   ______________________________________                                         X means presence of undefined residues; aa. 6 and 9 of the Nterminal            sequence may be either Glu or Gln. .sup.1 SEQ ID N1; .sup.2 SEQ ID N2;         .sup.3 SEQ ID N3; .sup.4 SEQ ID N4; .sup.5 SEQ ID N5                     

Example 2 Nucleotide Amplification, Sequencing and Cloning

Two independent oligonucleotides are synthesized on the basis of the N-terminal sequence (N-A and N-B). A third oligonucleotide (Int) is sythesized on the basis of the peptide P-3 sequence, starting from the first nucleotide coding for aa. 6 (Pro) to the second nucleotide coding for aa. 11 (Gln). The nucleotide sequences are shown in the following Table 2.

Table 2

Primer oligonucleotides for amplification reaction and corresponding amino acid sequence

4-10 N-terminal sequence (N-A) ##STR1##

14-21 N-terminal sequence (N-B) ##STR2##

6-11 P-3 peptide sequence (Int) ##STR3##N means one of the four nucleotides.

N-A, N-B and Int oligonucleotides are used as primers of a polymerase chainreaction (PCR) using genomic DNA, extracted from Phaseolus vulgaris, Pinto cultivar, as template, by conventional methods (7). Polymerizing reactionsare carried out on Perkin Elmer/Cetus equipment according to manufacturer'sinstructions. The primer hybridization is carried out at 45° C. or 50° C., depending upon using respectively degenerate or nondegenerate nucleotides. The polymerization enzyme (Amplitaq, Perkin Elmer) is used at 1 U/40 μl of reaction mix. PCR products are fractionated on a 0.8% agarose gel and dyed with ethidium bromide.

A clear DNA band of appr. 0.79 kb, defined as PGIP-1, is observed (FIG. 2, line c), when using the N-A oligo. The band is missing in control reactions (FIG. 2, lines b, e, q). By using N-D and Int oligos as primers,the DNA product (PGIP-2) is of appr. 0.76 kb, i.e. 30 bp shorter than PGIP-1 (FIG. 2, line d).

The agarose gel is transferred to nitrocellulose membrane and probed with PGIP-2, previously eluted from the agarose gel and amplified with 6 PCR cycles in presence of P³² ATP. PGIP-1 and PGIP-2 sequences hybridizedwith the same intensity to the radiolabelled probe. FIG. 3 shows a scheme of oligonucleotides and PCR obtained products.

The PGIP-2 fragment, eluted from the agarose gel and further amplified by PCR using N-B and Int oligonucleotides, is purified by removing the low melting point agarose and inserted into the pGEM7zf(+) vector (Promega) byconventional methods. The recombinant vector, containing the whole DNA fragment of PGIP-2, is defined as pPT-1.

The pPt-1 insert is sequenced and an open reading frame of 252 amino acids is deduced. As expected the amino acid sequence comprises sequences corresponding to the 14-21 N-terminal and to the P-3 peptide as well. Moreover it comprises sequences of the P-1, P-2 and P-4 peptides.

Example 3 Isolation of a Genomic PGIP Clone

A genomic DNA library from the Saxa cultivar of Phaseolus vulgaris, obtained by partial digestion with restriction enzyme MboI, into the EMBL3lambda vector, has been supplied by Clontech (Ca, USA). The library is probed by PCR and plaque-hybridization combination. 5×10⁵ recombinant phages are probed by conventional plaque-hybridization, as described in (7), by using the radiolabelled p-PT1 insert. Positive clonesare grouped in three different classes, to be further analyzed with PCR. PCR screening is performed using crude phage DNA as template and two nondegenerate primers (P21 and P22), synthesized on the basis of the p-PT1insert sequence, whose sequences are as follows: P21: AAGGCTCTGTTCAGTTGCTT (SEQ ID N12); P22:CTATACATTGGCGGCATCAAT (SEQ ID N13). Positive clones havean expected 378 bp amplification fragment. The first class shows strong hybridization signals and is able to amplify the 378 bp fragment. The second class also shows strong hybridization signals, but amplification products from PCR are not observed. The third class shows a weaker hybridization, but gives rise to specific amplification products from PCR,other than the 378 bp fragment. Among positive clones of the first class, one clone (lambda PGIP-3.3. insert=17 kb) is selected and isolated for further analysis. A 3.3 kb SalI--SalI fragment is shown to contain the PGIP gene, as demonstrated by Southern blot analysis and PCR experiments. The fragments is subcloned in the SalI site of the Bluescript SK⁺ plasmid (Stratagene), resulting in a recombinant plasmid named pPt-2. The orientation and the position of the PGIP gene in the 3.3 kb cloned fragment is defined by PCR (FIG. 4), using different combination of both plasmid (T3 and T7) and PTGP specific primers (FIG. 4). It is calculated that the 3.3 kb SalI--SalI fragment comprises appr. 1860 nt upstream the first ATG, 1026 nt of coding region and 97 nt of the 3'-untranslated region, with appr. 450 nt adjacent sequences. A partial restriction map ofthe 17 kb genomic insert, the orientation and the PGIP position in the pPT-2 subclone are shown in FIG. 4.

Both DNA strands of the PGIP gene are sequenced; the sequence strategy is shown in FIG. 4. The whole nucleotide sequence of the PGIP coding region and of the untranslated 3' region (1116 nt) is reported in SEQ ID N14. Thepolyadenylation site is 97 bp downstream of the TAA stop codon. Three sequences, corresponding to putative eukaryotic polyadenylation signals, are at 42, 22 and 16 nt upstream of the polyadonylation site respectively.A comparative analysis between the genomic sequence and the relevant cDNA sequence above that no introns are present in the 345 nucleotide 3'-end gene region. Further analysis shows that no introns are present for the whole PGIP gene, as confirmed by PCR experiments. The PGIP gene DNA sequence defines a 342 amino acid PGIP protein (see SEQ ID N14 and N15). Neither the nucleotide or amino acid sequences show any significant homology with any known sequence.

A hydrophobicity plot of the PGIP protein is shown in FIG. 5. The sequence includes four potential glycosylation sites.

Example 4 Northern Blot Analysis

PGIP specific mRNA levels are analysed in different plant tissues. The pPT1purified insert is used to probe polyA⁺ RNA, isolated from either hypocotyls, or leaves, or flowers or suspension cultured cells of Phaseolus vulgaris, Pinto cultivar. A single 1,2 kb transcript is identified in mRNA from suspension cultured cells. The fragment is also present in other tissues, even if minor amount.

PCR experiments, using single-strand cDNA from suspension cultured cells and P-21 and P-22 as templates, shows the expected amplification of the 370 bp fragment, thus indicating that at least a fraction of the PGIP geneexpression in cultured cells may be ascribed to the cloned and characterized gene.

Example 5 Analysis of PGIP Genes From Two Different Phaseolus vulgaris cultivars

A cDNA library is made in the lambda gt11 vector from polyA³⁰ RNA, purified from suspension cultured cells of Phaseolus vulgaris, Pinto cultivar. By probing the cDNA library wit pPT1, a cDNA recombinant clone (lambda AD-1) containing PGIP coding sequences is isolated. The lambda AD-1 insert (842 bp) is subcloned in the Bluescript SK+ vector, named pAD-1, deposited at DSM, Germany, with the n. 6821, and sequenced. The insert represents a whole PGIP cDNA fragment and includes the polyA tail. The sequence of the pAD-1 insert is shown in SEQ ID N16. When compared to SEQ ID N14, the pAD-1 insert refers to sequence from 345 to 1116 nt of SEQID N14. A comparative analysis between the genomic clone from Saxa cultivarand the cDNA clone from Pinto cultivar shows a 96.4% homology of nucleotidesequence and a 97.4% homology of amino acid sequence (FIG. 7).

This invention has been described with reference to some preferred embodiments; however it is understood that any changes and/or modificationcould be made by anyone skilled in the art, remaining within the scope of the claims.

REFERENCES

1) Cooper, R. M. In: Plant Disease: Infection, Damage and Loss. Wood, R. K.S. & Jellis, G. J. eds, Oxford, Blackwell Scientific Publications, pp. 13-27 (1984).

2) Hahn, M. G. Bucheli, P., Cervone F., Doares, S. H., Darvill, A. G. and Albersheim, P. In: Plant-Microbe Interaction, Vol. 3, Nester, E. and Kosuge, T., eds, New York, MacMillan Press, pp. 131-181 (1989).

3) Salvi, G., Giarizzo, F., De Lorenzo, G. and Cervone, F. J. Plant Physiol, 136, 513-518 (1990).

4) Cervone, F., De Lorenzo, G. Pressey, R., Darvill, A., and Albersheim, P.Phytochemistry 29, 447-449 (1990).

5) Cervone F., Hahn, N. G., De Lorenzo, G., Darvill, A. and Albersheim, P. Plant Physiology, 90, 542-548 (1989).

6) Degra, L, Salvi, G., Mariotti, D., De Lorenzo, G. and Cervone, F. J. Plant Physiol., 133, 364-366 (1988).

7) Sambrook, D., Fritsch, E. F., Naniatis, T. In: Molecular Cloning: A Laboratory Manual, 2nd ed., vols.1, 2, 3, CSH Lab Press (1989).

    __________________________________________________________________________     SEQUENCE LISTING                                                               (1) GENERAL INFORMATION:                                                       (iii) NUMBER OF SEQUENCES: 17                                                  (2) INFORMATION FOR SEQ ID NO:1:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 21 amino acids                                                     (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: unknown                                                          (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:                                        GluLeuXaaAsnProGlxAspLysGlxAlaLeuLeuXaaIleLysLys                               151015                                                                         AspLeuGlyAsnPro                                                                20                                                                             (2) INFORMATION FOR SEQ ID NO:2:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 5 amino acids                                                      (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:                                        IleHisLeuAlaLys                                                                15                                                                             (2) INFORMATION FOR SEQ ID NO:3:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 5 amino acids                                                      (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:                                        LeuPheThrSerMet                                                                15                                                                             (2) INFORMATION FOR SEQ ID NO:4:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 13 amino acids                                                     (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:                                        IleTrpXaaThrLeuProGlnGlyLeuThrGlnLeuLys                                        1510                                                                           (2) INFORMATION FOR SEQ ID NO:5:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 12 amino acids                                                     (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:                                        IleSerGlyAlaIleProAspSerTyrGlySerPhe                                           1510                                                                           (2) INFORMATION FOR SEQ ID NO:6:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 7 amino acids                                                      (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:                                        AsnProGlxAspLysGlxAla                                                          15                                                                             (2) INFORMATION FOR SEQ ID NO:7:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 20 base pairs                                                      (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: synthetic primer/probe                                     (iii) HYPOTHETICAL: YES                                                        (iv) ANTI-SENSE: NO                                                            (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:                                        AAYCCNSARGAYAARSARCC20                                                         (2) INFORMATION FOR SEQ ID NO:8:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 8 amino acids                                                      (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:                                        IleLysLysAspLeuGlyAsnPro                                                       15                                                                             (2) INFORMATION FOR SEQ ID NO:9:                                               (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 23 base pairs                                                      (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: synthetic primer/probe                                     (iii) HYPOTHETICAL: YES                                                        (iv) ANTI-SENSE: NO                                                            (xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:                                        ATHAARAARGAYYTNGGNAAYCC23                                                      (2) INFORMATION FOR SEQ ID NO:10:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 6 amino acids                                                      (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: peptide                                                    (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:                                       ProGlnGlyLeuThrGln                                                             15                                                                             (2) INFORMATION FOR SEQ ID NO:11:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 17 base pairs                                                      (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: synthetic primer/probe                                     (iii) HYPOTHETICAL: YES                                                        (iv) ANTI-SENSE: NO                                                            (xi) SEQUENCE DESCRIPTION: SEQ ID NO:11:                                       GGNGTYCCNRANTGNGT17                                                            (2) INFORMATION FOR SEQ ID NO:12:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 20 base pairs                                                      (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: synthetic primer/probe                                     (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (vii) IMMEDIATE SOURCE:                                                        (B) CLONE: P21                                                                 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:12:                                       AAGGCTCTGTTCAGTTGCTT20                                                         (2) INFORMATION FOR SEQ ID NO:13:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 21 base pairs                                                      (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: synthetic primer/probe                                     (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (vii) IMMEDIATE SOURCE:                                                        (B) CLONE: P22                                                                 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:13:                                       CTATACATTGGCGGCATCAAT21                                                        (2) INFORMATION FOR SEQ ID NO:14:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 1116 base pairs                                                    (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: double                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: DNA (genomic)                                              (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Saxa                                                               (vii) IMMEDIATE SOURCE:                                                        (B) CLONE: lambda PGIP-3.3                                                     (ix) FEATURE:                                                                  (A) NAME/KEY: CDS                                                              (B) LOCATION: 1..1026                                                          (ix) FEATURE:                                                                  (A) NAME/KEY: 3'UTR                                                            (B) LOCATION: 1027..1116                                                       (xi) SEQUENCE DESCRIPTION: SEQ ID NO:14:                                       ATGACTCAATTCAATATCCCAGTAACCATGTCTTCAAGCTTAAGCATA48                             MetThrGlnPheAsnIleProValThrMetSerSerSerLeuSerIle                               151015                                                                         ATTTTGGTCATTCTTGTATCTTTGAGAACTGCACTCTCAGAGCTATGC96                             IleLeuValIleLeuValSerLeuArgThrAlaLeuSerGluLeuCys                               202530                                                                         AACCCACAAGATAAGCAAGCCCTTCTCCAAATCAAGAAAGACCTTGGC144                            AsnProGlnAspLysGlnAlaLeuLeuGlnIleLysLysAspLeuGly                               354045                                                                         AACCCAACCACTCTCTCTTCATGGCTTCCAACCACCGACTGTTGTAAC192                            AsnProThrThrLeuSerSerTrpLeuProThrThrAspCysCysAsn                               505560                                                                         AGAACCTGGCTAGGTGTTTTATGCGACACCGACACCCAAACATATCGC240                            ArgThrTrpLeuGlyValLeuCysAspThrAspThrGlnThrTyrArg                               65707580                                                                       GTCAACAACCTCGACCTCTCCGGCCATAACCTCCCAAAACCCTACCCT288                            ValAsnAsnLeuAspLeuSerGlyHisAsnLeuProLysProTyrPro                               859095                                                                         ATCCCTTCCTCCCTCGCCAACCTCCCCTACCTCAATTTTCTATACATT336                            IleProSerSerLeuAlaAsnLeuProTyrLeuAsnPheLeuTyrIle                               100105110                                                                      GGCGGCATCAATAACCTCGTCGGTCCAATCCCCCCCGCCATCGCTAAA384                            GlyGlyIleAsnAsnLeuValGlyProIleProProAlaIleAlaLys                               115120125                                                                      CTCACCCAACTCCACTATCTCTATATCACTCACACCAATGTCTCCGGC432                            LeuThrGlnLeuHisTyrLeuTyrIleThrHisThrAsnValSerGly                               130135140                                                                      GCAATACCCGATTTCTTGTCACAGATCAAAACCCTCGTCACCCTCGAC480                            AlaIleProAspPheLeuSerGlnIleLysThrLeuValThrLeuAsp                               145150155160                                                                   TTCTCCTACAACGCCCTCTCCGGCACCCTCCCTCCCTCCATCTCTTCT528                            PheSerTyrAsnAlaLeuSerGlyThrLeuProProSerIleSerSer                               165170175                                                                      CTCCCCAACCTCGGAGGAATCACATTCGACGGCAACCGAATCTCCGGC576                            LeuProAsnLeuGlyGlyIleThrPheAspGlyAsnArgIleSerGly                               180185190                                                                      GCCATCCCCGACTCCTACGGCTCGTTTTCGAAGCTGTTTACGGCGATG624                            AlaIleProAspSerTyrGlySerPheSerLysLeuPheThrAlaMet                               195200205                                                                      ACCATCTCCCGCAACCGCCTCACCGGGAAGATTCCACCGACGTTTGCG672                            ThrIleSerArgAsnArgLeuThrGlyLysIleProProThrPheAla                               210215220                                                                      AATCTGAACCTGGCGTTCGTTGACTTGTCTCGGAACATGCTGGAGGGT720                            AsnLeuAsnLeuAlaPheValAspLeuSerArgAsnMetLeuGluGly                               225230235240                                                                   GACGCGTCGGTGTTGTTCGGGTCAGATAAGAACACGAAGAAGATACAT768                            AspAlaSerValLeuPheGlySerAspLysAsnThrLysLysIleHis                               245250255                                                                      CTGGCGAAGAACTCTCTTGCTTTTGATTTGGGGAAAGTGGGGTTGTCA816                            LeuAlaLysAsnSerLeuAlaPheAspLeuGlyLysValGlyLeuSer                               260265270                                                                      AAGAACTTGAACGGGTTGGATCTGAGGAACAACCGTATCTATGGAACG864                            LysAsnLeuAsnGlyLeuAspLeuArgAsnAsnArgIleTyrGlyThr                               275280285                                                                      CTACCTCAGGGACTAACGCAGCTAAAGTTTCTGCAAAGTTTAAATGTG912                            LeuProGlnGlyLeuThrGlnLeuLysPheLeuGlnSerLeuAsnVal                               290295300                                                                      AGCTTCAACAATCTGTGCGGTGAGATTCCTCAAGGTGGGAACTTGAAA960                            SerPheAsnAsnLeuCysGlyGluIleProGlnGlyGlyAsnLeuLys                               305310315320                                                                   AGGTTTGACGTTTCTTCTTATGCCAACAACAAGTGCTTGTGTGGTTCT1008                           ArgPheAspValSerSerTyrAlaAsnAsnLysCysLeuCysGlySer                               325330335                                                                      CCTCTTCCTTCCTGCACTTAACCATTTCCAGATTCGGTAATTATGGAT1056                           ProLeuProSerCysThr                                                             340                                                                            GCATCATGTTTGCCTTTCTATGAACATCAATAATGATACAAGTGTAAAAATAAAAAATTA1116               (2) INFORMATION FOR SEQ ID NO:15:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 342 amino acids                                                    (B) TYPE: amino acid                                                           (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: protein                                                    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:15:                                       MetThrGlnPheAsnIleProValThrMetSerSerSerLeuSerIle                               151015                                                                         IleLeuValIleLeuValSerLeuArgThrAlaLeuSerGluLeuCys                               202530                                                                         AsnProGlnAspLysGlnAlaLeuLeuGlnIleLysLysAspLeuGly                               354045                                                                         AsnProThrThrLeuSerSerTrpLeuProThrThrAspCysCysAsn                               505560                                                                         ArgThrTrpLeuGlyValLeuCysAspThrAspThrGlnThrTyrArg                               65707580                                                                       ValAsnAsnLeuAspLeuSerGlyHisAsnLeuProLysProTyrPro                               859095                                                                         IleProSerSerLeuAlaAsnLeuProTyrLeuAsnPheLeuTyrIle                               100105110                                                                      GlyGlyIleAsnAsnLeuValGlyProIleProProAlaIleAlaLys                               115120125                                                                      LeuThrGlnLeuHisTyrLeuTyrIleThrHisThrAsnValSerGly                               130135140                                                                      AlaIleProAspPheLeuSerGlnIleLysThrLeuValThrLeuAsp                               145150155160                                                                   PheSerTyrAsnAlaLeuSerGlyThrLeuProProSerIleSerSer                               165170175                                                                      LeuProAsnLeuGlyGlyIleThrPheAspGlyAsnArgIleSerGly                               180185190                                                                      AlaIleProAspSerTyrGlySerPheSerLysLeuPheThrAlaMet                               195200205                                                                      ThrIleSerArgAsnArgLeuThrGlyLysIleProProThrPheAla                               210215220                                                                      AsnLeuAsnLeuAlaPheValAspLeuSerArgAsnMetLeuGluGly                               225230235240                                                                   AspAlaSerValLeuPheGlySerAspLysAsnThrLysLysIleHis                               245250255                                                                      LeuAlaLysAsnSerLeuAlaPheAspLeuGlyLysValGlyLeuSer                               260265270                                                                      LysAsnLeuAsnGlyLeuAspLeuArgAsnAsnArgIleTyrGlyThr                               275280285                                                                      LeuProGlnGlyLeuThrGlnLeuLysPheLeuGlnSerLeuAsnVal                               290295300                                                                      SerPheAsnAsnLeuCysGlyGluIleProGlnGlyGlyAsnLeuLys                               305310315320                                                                   ArgPheAspValSerSerTyrAlaAsnAsnLysCysLeuCysGlySer                               325330335                                                                      ProLeuProSerCysThr                                                             340                                                                            (2) INFORMATION FOR SEQ ID NO:16:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 792 base pairs                                                     (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: double                                                       (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: cDNA                                                       (iii) HYPOTHETICAL: NO                                                         (iv) ANTI-SENSE: NO                                                            (vi) ORIGINAL SOURCE:                                                          (A) ORGANISM: Phaseolus vulgaris                                               (B) STRAIN: Pinto                                                              (vii) IMMEDIATE SOURCE:                                                        (B) CLONE: pAD-1 (DSM No.6821)                                                 (ix) FEATURE:                                                                  (A) NAME/KEY: CDS                                                              (B) LOCATION: 2..685                                                           (ix) FEATURE:                                                                  (A) NAME/KEY: 3'UTR                                                            (B) LOCATION: 686..792                                                         (xi) SEQUENCE DESCRIPTION: SEQ ID NO:16:                                       CAATAACCTCGTCGGTCCAATCCCCCCCGCCATCGCTAAACTCACC46                               AsnAsnLeuValGlyProIleProProAlaIleAlaLysLeuThr                                  151015                                                                         CAACTCCACTATCTCTATATCACCCACACCAATGTCTCCGGCGCAATA94                             GlnLeuHisTyrLeuTyrIleThrHisThrAsnValSerGlyAlaIle                               202530                                                                         CCCGATTTCTTGTCACAGATCAAAACCCTCGTCACCCTCGACTTCTCC142                            ProAspPheLeuSerGlnIleLysThrLeuValThrLeuAspPheSer                               354045                                                                         TACAACGCCCTCTCCGGCACCCTACCTCCCTCCATCTCTTCTCTCCCC190                            TyrAsnAlaLeuSerGlyThrLeuProProSerIleSerSerLeuPro                               505560                                                                         AACCTCGTAGGAATCACATTCGACGGCAACCGAATCTCCGGCGCCATC238                            AsnLeuValGlyIleThrPheAspGlyAsnArgIleSerGlyAlaIle                               657075                                                                         CCCGACTCCTACGGCTCATTTTCGAAGCTGTTCACGTCGATGACCATC286                            ProAspSerTyrGlySerPheSerLysLeuPheThrSerMetThrIle                               80859095                                                                       TCCCGCAACCGCCTCACCGGGAAGATTCCGCCGACGTTTGCGAATCTG334                            SerArgAsnArgLeuThrGlyLysIleProProThrPheAlaAsnLeu                               100105110                                                                      AACCTGGCGTTCGTTGACTTGTCTCGAAACATGCTGCAGGGTGACGCG382                            AsnLeuAlaPheValAspLeuSerArgAsnMetLeuGlnGlyAspAla                               115120125                                                                      TCGGTGTTGTTCGGATCAGATAAGAACACGCAGAAGATACATCTGGCG430                            SerValLeuPheGlySerAspLysAsnThrGlnLysIleHisLeuAla                               130135140                                                                      AAGAACTCTCTTGCTTTTGATTTGGAGAAAGTGGGGTTGTCAAAGAAC478                            LysAsnSerLeuAlaPheAspLeuGluLysValGlyLeuSerLysAsn                               145150155                                                                      TTGAACGGGTTGGATCTGAGGAACAACCGTATCTATGGGACGCTACCG526                            LeuAsnGlyLeuAspLeuArgAsnAsnArgIleTyrGlyThrLeuPro                               160165170175                                                                   CAGGGACTGACGCAGCTAAAGTTTCTGCACAGTTTAAATGTGAGCTTC574                            GlnGlyLeuThrGlnLeuLysPheLeuHisSerLeuAsnValSerPhe                               180185190                                                                      AACAATCTGTGCGGTGAGATTCCTCAAGGTGGGAACTTGCAAACATTT622                            AsnAsnLeuCysGlyGluIleProGlnGlyGlyAsnLeuGlnThrPhe                               195200205                                                                      CACGTTTCTGCTTATGCCAACAACAAGTGCTTGTGTGGTTCTCCTCTT670                            HisValSerAlaTyrAlaAsnAsnLysCysLeuCysGlySerProLeu                               210215220                                                                      CCTGCCTGCACTTAATCATTTCCAGATTCGGTAATTATGGATGCATCATGTT722                        ProAlaCysThr                                                                   225                                                                            TGCCTTTCTATGAACATCAATAATGATACAAGTTTAAATAAAAATAAATTTATGAAATAA782                AAAAAAAAAA792                                                                  (2) INFORMATION FOR SEQ ID NO:17:                                              (i) SEQUENCE CHARACTERISTICS:                                                  (A) LENGTH: 227 amino acids                                                    (B) TYPE: amino acid                                                           (D) TOPOLOGY: linear                                                           (ii) MOLECULE TYPE: protein                                                    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:17:                                       AsnAsnLeuValGlyProIleProProAlaIleAlaLysLeuThrGln                               151015                                                                         LeuHisTyrLeuTyrIleThrHisThrAsnValSerGlyAlaIlePro                               202530                                                                         AspPheLeuSerGlnIleLysThrLeuValThrLeuAspPheSerTyr                               354045                                                                         AsnAlaLeuSerGlyThrLeuProProSerIleSerSerLeuProAsn                               505560                                                                         LeuValGlyIleThrPheAspGlyAsnArgIleSerGlyAlaIlePro                               65707580                                                                       AspSerTyrGlySerPheSerLysLeuPheThrSerMetThrIleSer                               859095                                                                         ArgAsnArgLeuThrGlyLysIleProProThrPheAlaAsnLeuAsn                               100105110                                                                      LeuAlaPheValAspLeuSerArgAsnMetLeuGlnGlyAspAlaSer                               115120125                                                                      ValLeuPheGlySerAspLysAsnThrGlnLysIleHisLeuAlaLys                               130135140                                                                      AsnSerLeuAlaPheAspLeuGluLysValGlyLeuSerLysAsnLeu                               145150155160                                                                   AsnGlyLeuAspLeuArgAsnAsnArgIleTyrGlyThrLeuProGln                               165170175                                                                      GlyLeuThrGlnLeuLysPheLeuHisSerLeuAsnValSerPheAsn                               180185190                                                                      AsnLeuCysGlyGluIleProGlnGlyGlyAsnLeuGlnThrPheHis                               195200205                                                                      ValSerAlaTyrAlaAsnAsnLysCysLeuCysGlySerProLeuPro                               210215220                                                                      AlaCysThr                                                                      225                                                                            __________________________________________________________________________ 

We claim:
 1. An isolated DNA fragment, or the complement thereof, encoding a protein having an inhibiting activity for a fungal polygalacturonase enzyme derived from Phaseolus plants, parts thereof or cultured plant cells of a plant of the genus Phaseolus.
 2. An isolated DNA fragment according to claim 1 wherein said Phaseolus plant is of the species Phaseolus vulgaris.
 3. An isolated DNA fragment according to claim 1 which encodes a protein comprising the amino acid sequence of SEQ ID No. 15 or SEQ ID No.
 17. 4. An isolated DNA according to claim 3 which encodes a protein comprising the amino acid sequence of SEQ ID N15 extending from amino acid 1 to amino acid
 342. 5. An isolated DNA according to claim 4 which encodes a protein having the amino acid sequence of SEQ ID N15.
 6. An isolated DNA according to claim 3 which encodes a protein having the amino acid sequence of SEQ ID N15 extending from amino acid 1 to amino acid
 342. 7. An isolated DNA fragment, or complement thereof, which encodes a protein derived from plants, parts thereof or cultured plant cells, said protein having an inhibitory activity for a fungal polygalacturonase enzyme and comprising a substituted SEQ ID No. 15 in which up to nine amino acids are substituted.
 8. An isolated DNA fragment according to claim 7 which encodes a protein comprising the amino acid sequence of SEQ ID N17.
 9. An isolated DNA fragment according to claim 1 comprising the coding region from nucleotide 1 to nucleotide 1026 of SEQ ID No. 14 or the coding region from nucleotide 2 to 685 of SEQ ID No.
 16. 10. An isolated DNA fragment according to claim 9 further comprising a 3'-untranslated sequence from nucleotide 1027 to nucleotide 1116 of SEQ ID N14.
 11. An isolated DNA fragment according to claim 1 comprising an allele of either SEQ ID N14 or SEQ ID N16 sequences.
 12. A plant transformed with a DNA fragment according to claim 1 to thereby produce a PGIP protein having an inhibiting activity for a fungal PG enzyme.
 13. A plant according to claim 12 which prior to transformation does not produce said PGIP protein.
 14. The plant of claim 12 that is a dicot.
 15. A recombinant vector comprising a DNA fragment according to claim
 1. 16. A recombinant vector according to claim 15 wherein the vector is of plasmid or phage origin.
 17. A recombinant vector comprising a DNA fragment according to claim
 3. 18. A recombinant vector according to claim 17 wherein said vector is the pAD-1 plasmid.
 19. A recombinant vector according to claim 15 wherein said vector comprises a promoter capable of expressing said coding PGIP nucleotide sequence.
 20. A recombinant vector according to claim 19 wherein said promoter is active in bacteria, in yeasts or in higher plants.
 21. Cells transformed by a vector according to claim
 15. 22. Cells according to claim 21 which are bacterial cells.
 23. Cells according to claim 22 which are of the species Escherichia coli.
 24. Cells according to claim 21 which are higher plant cells.
 25. Cells according to claim 21 which are yeast cells.
 26. An isolated DNA fragment according to claim 7 wherein said plant is a plant of the genus Phaseolus.
 27. An isolated DNA fragment according to claim 26 wherein said plant is of the species Phaseolus vulgaris.
 28. A plant transformed with a DNA fragment according to claim 3 to thereby produce a PGIP protein having an inhibiting activity for a fungal PG system.
 29. A plant transformed with a DNA fragment according to claim 7 to thereby produce a PGIP protein having an inhibiting activity for a fungal PG enzyme.
 30. A process for making a plant which produces an increased level of PGIP which comprises transforming said plant with a DNA fragment according to claim 1 such that PGIP is thereby produced.
 31. A process for making a plant which produces an increased level of PGIP which comprises transforming said plant with a DNA fragment according to claim 3 such that PGIP is thereby produced.
 32. A process for making a plant which produces an increased level of PGIP which comprises transforming said plant with a DNA fragment according to claim 7 such that PGIP is thereby produced.
 33. A recombinant vector comprising a DNA fragment according to claim
 7. 34. Cells transformed by a vector according to claim
 17. 35. Cells transformed by a vector according to claim
 33. 